Some examples of why this was wrong:
1. Cmd-Tab lets me select a hidden window but it won't show it!
2. Many frequently used click targets are too small. For example, the close, minimise and maximise buttons.
3. The close minimise and maximise buttons reveal their functions only when the mouse is over them.
4. There's no reliable way to maximise a window.
5. Despite really trying to go keyboard-only, it's very difficult to avoid using the mouse.
6. The file browser doesn't show the aggregate size of selected files.
7. Cmd+Down to open the selected file! Why not Enter?!
8. I still have no idea which button Enter will press on a dialog box. There seems no way to make this clearer or to activate something like Alt+underlined_letter_of_desired_button_caption.
9. There's no Cut operation, only Copy and Paste.
My MacBook Pro is awesome hardware but Windows is way ahead of OSX.